How to Dump an Object's Fields to the Console

How do I dump an object's fields to the console?

Possibly:

puts variable.inspect

How to fully dump / print variable to console in the Dart language?

There is no built in function that generates such an output.

print(variable) prints variable.toString() and Instance of 'FooBarObject' is the default implementation. You can override it in custom classes and print something different.

You can use reflection (https://www.dartlang.org/articles/libraries/reflection-with-mirrors) to build a function yourself that investigates all kinds of properties of an instance and prints it the way you want.
There is almost no limitation of what you can do and for debugging purposes it's definitely a fine option.

For production web application it should be avoided because it limits tree-shaking seriously and will cause the build output size to increase notable.
Flutter (mobile) doesn't support reflection at all.

You can also use one of the JSON serialization packages, that make it easy to add serialization to custom classes and then print the serialized value.
For example

• https://pub.dartlang.org/packages/dson

I think there are others, but I don't know about (dis)advantages, because I usually roll my own using https://pub.dartlang.org/packages/source_gen

What is the best way to dump entire objects to a log in C#?

You could base something on the ObjectDumper code that ships with the Linq samples.

Have also a look at the answer of this related question to get a sample.

How can I display a JavaScript object?

If you want to print the object for debugging purposes, use the code:

var obj = {
  prop1: 'prop1Value',
  prop2: 'prop2Value',
  child: {
    childProp1: 'childProp1Value',
  },
}
console.log(obj)

will display:

Note: you must only log the object. For example, this won't work:

console.log('My object : ' + obj)

Note ': You can also use a comma in the log method, then the first line of the output will be the string and after that, the object will be rendered:

console.log('My object: ', obj);

Dumping a java object's properties

You could try XStream.

XStream xstream = new XStream(new Sun14ReflectionProvider(
  new FieldDictionary(new ImmutableFieldKeySorter())),
  new DomDriver("utf-8"));
System.out.println(xstream.toXML(new Outer()));

prints out:

<foo.ToString_-Outer>
  <intValue>5</intValue>
  <innerValue>
    <stringValue>foo</stringValue>
  </innerValue>
</foo.ToString_-Outer>

You could also output in JSON

And be careful of circular references ;)

How can I get the full object in Node.js's console.log(), rather than '[Object]'?

You need to use util.inspect():

const util = require('util')

console.log(util.inspect(myObject, {showHidden: false, depth: null, colors: true}))

// alternative shortcut
console.log(util.inspect(myObject, false, null, true /* enable colors */))

Outputs

{ a: 'a',  b: { c: 'c', d: { e: 'e', f: { g: 'g', h: { i: 'i' } } } } }

Grails: How to dump an object's properties?

You can try use to render the object as JSON instead of using making it implicitly call toString(). I think it will render the structure of the object properly.

Is there a built-in function to print all the current properties and values of an object?

You are really mixing together two different things.

Use dir(), vars() or the inspect module to get what you are interested in (I use __builtins__ as an example; you can use any object instead).

>>> l = dir(__builtins__)
>>> d = __builtins__.__dict__

Print that dictionary however fancy you like:

>>> print l
['ArithmeticError', 'AssertionError', 'AttributeError',...

or

>>> from pprint import pprint
>>> pprint(l)
['ArithmeticError',
 'AssertionError',
 'AttributeError',
 'BaseException',
 'DeprecationWarning',
...

>>> pprint(d, indent=2)
{ 'ArithmeticError': <type 'exceptions.ArithmeticError'>,
  'AssertionError': <type 'exceptions.AssertionError'>,
  'AttributeError': <type 'exceptions.AttributeError'>,
...
  '_': [ 'ArithmeticError',
         'AssertionError',
         'AttributeError',
         'BaseException',
         'DeprecationWarning',
...

Pretty printing is also available in the interactive debugger as a command:

(Pdb) pp vars()
{'__builtins__': {'ArithmeticError': <type 'exceptions.ArithmeticError'>,
                  'AssertionError': <type 'exceptions.AssertionError'>,
                  'AttributeError': <type 'exceptions.AttributeError'>,
                  'BaseException': <type 'exceptions.BaseException'>,
                  'BufferError': <type 'exceptions.BufferError'>,
                  ...
                  'zip': <built-in function zip>},
 '__file__': 'pass.py',
 '__name__': '__main__'}

How to print struct variables in console?

To print the name of the fields in a struct:

fmt.Printf("%+v\n", yourProject)

From the fmt package:

when printing structs, the plus flag (%+v) adds field names

That supposes you have an instance of Project (in 'yourProject')

The article JSON and Go will give more details on how to retrieve the values from a JSON struct.

---

This Go by example page provides another technique:

type Response2 struct {
  Page   int      `json:"page"`
  Fruits []string `json:"fruits"`
}

res2D := &Response2{
    Page:   1,
    Fruits: []string{"apple", "peach", "pear"}}
res2B, _ := json.Marshal(res2D)
fmt.Println(string(res2B))

That would print:

{"page":1,"fruits":["apple","peach","pear"]}

---

If you don't have any instance, then you need to use reflection to display the name of the field of a given struct, as in this example.

type T struct {
    A int
    B string
}

t := T{23, "skidoo"}
s := reflect.ValueOf(&t).Elem()
typeOfT := s.Type()

for i := 0; i < s.NumField(); i++ {
    f := s.Field(i)
    fmt.Printf("%d: %s %s = %v\n", i,
        typeOfT.Field(i).Name, f.Type(), f.Interface())
}

---

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